Slack-adjuster.



PATENTED JULY 16, 1907,

A. PARKER-SMITH.

SLACK ADJUSTER.

APPLICATION FILED NOV.21,190B.

W awuc u-boz V QXMWMM UNITED STATES PATENT OFFICE.

', AUGUSTUS PARKER-SMITH, OF- NEVYORK, N. Y., ASSIGNOR TO ATLAS SLACK ADJUSTER COMPANY, A CORPORATION OF NEW YORK.

SLACK-ADJUSTER.

s Specification of Letters Patent.

' Patented July 16, 1907.

, To all whom it may concern."

Be it known that I, AUGUSTUS PARKER-SMI'rma citizen ofthe United States of America, and a resident of the borough of Manhattan, city, county, and State" of New York; have invented certain new and f useful Improvements in Slack-Adjusters, of which the following is a specification.

My invention relates to mechanism for automatically adjusting the brake rigging on a railway or other dicate like parts. L

car so that a uniform maximum of travel of the piston will be preserved as the brake shoes wear down.

- 1 is the car truck having wheels 2, 2, on which are applied the brake shoes 3, 3, by means of the brake beams 4 and 5, the ordinary dead lever 6, live lever 7 and top rod 8.

" In place of the ordinary bottom rod, I employ the telescoping bottom rod composed of the stirrup 9 pivoted to the dead lever and having the perforated clutch dog 10 mounted therein and fulcrumed on the beveled corner 11 and the second or telescoping portion 12 of which is pivoted to the live lever and passes through a perforation in the outer end of the stirrup 9 and through the perforated clutch dog 10. This produces a telescoping bottom rod which can be lengthened by merely pulling the parts away from 7 one another, but which normally cannot be shortened,

I I nection to one of the brake beams.

the clutch dog holding to prevent. the rod 12 from being forced into the stirrup 9. The clutch dog is held up..to its work by spring 22/. The brake beams 4 and 5 are connected by a take-up device which also comprises a telescoping section and a lost motion coni As shown, this take-up device consists of the stirrup 13 fastened to the brake beam 5 and perforated at its outer end to permit of the passage of the rod 14. On this rod 14, which constitutes the other member of the telescopingsection, is mounted the perforated clutch dog 15, which is fulcrumed against the beveled portion 16 of the stirrup 13, and held in operative position by the spring 17. To the other brake beam 4 is fastened the metal strip or bar 18, which is bent twice at right portions 19 and 20 are perforated for the passage of the rod-14 and on said rod between them is located the stop 21.

The operation of my invention is as follows: The stop 21 is so proportioned with reference to the dis. tance between the sections 19 and 20 of the take-up device that the lost motion permitted to the rod 14 is: just that which the brake shoes should have -in a brake application in which the maximum allowable vibration of the live lever 7 occurs. If an excess movement of the live lever occurs, due to the wearing down of the brake shoes, the portion 20 of the bent strip 18 will strike the stop 21 and pullthe rod 14 through the clutch dog 15 a distance equal i.-

"the excess movement of the brake shoes over and above the predetermined limit. On release of the brakes, the live lever 7 willtend to return to its normal positionand in so'doing, will cause the stop 21 to strike againstthe portion 19 of the take-up device, bringing the rod 14 to a bearing on the clutch dog 15, and holding the brake beams further apart than they were before by an amount equal to the excess travel of the brake shoes on the previous application of brakes. Further movement of the live lever on its return will cause it to lengthen the bol tom rod by pulling out the telescoping joint and the dog 10 grasping the telescoping section 12 in its new position of adjustment, will serve to readjust'tho live lever and dead lever so that when the brakes are applied again only the standard maximum movement of the live lever will occur.

Among the advantages of my invention .niay be mentioned the factthat it accurately and exactly takes up the slack due to the wearing down of the brake shoes and does not take up the slack caused by springing of the brake rigging or by any change in position of the truck with reference to the car body.

' In short, my invention might be more accurately described as a brake shoe clearance adjusting mechanism. The pazticular form of friction clutch shown is an important feature of my invention as it will accurately take up the small allowance of motion occurring in this form of'mechanism. The mounting of the take-up device on the brake beams is also important as it produces a take-up action which is exactly equal to the excess movement of the brake shoes and A is not 'disturbed by any variation of the angularity-oi the live and dead levers such as occurs as the shoes weardown.

' Having, therefore, described my invention, I claim:

1. In a slack adjusting mechanism for railway brakes, the comblnatlon with the usual brake levers, rods and brake beams, of a telescoping bottom rod, the telescoping joint therein being provided with a friction clutch perstirruppivoted to oneilever, and having'a perforation in:

ffulcrumedon-an inner portion of thestirrup and a spring I it'souter-end-.-through which the other portion of the hot its outer end through which the other portion ofthe bottom rod pivoted to. the other lever passes, -a perforatedclutch dog mounted on said other portion of the rod-andmounted'ion said'rod and "compressed between said clutch dogaamt the outer portion: ofthe stirrup.

3. -In a slack adjusting mechanism for railway brakes; the combination .with the usual brake levers, .rods-a'nd brake beams, of a. telescoping bottom rod comprising a stirrupplvoted to one levei','and having a perforation in:

tom r0d--piV0fied':tQ' the other lever-passes,.a perforated clutch .dog mountedon said v otherportion .ot the rod and fulcrumed on an'inner portion of the stirrup and a springmountedon said-rod and compressed between said clutch dog-sand the outer portion of the stirrup, said fulcrum.

being; formed byga beveled shoulder in the stirrup.

*4; In aslack-adjusting mechanism for railway-brakes;- the'combinatlon with the usual brake levers, rods andbrnke beams, of a' telescoping bottom rod, means permit-'- ting the lengthening-of the bottom rod but normally pre-- venting the shortening thereof, and a take-up device comprising-a telescoping member connected at one end to one brake beam, and at the other end provided with a lost motion connection to the other brake beam, said lost -motionconnection comprising a bar fastened at one end to the brake beam, bent twice at right angles to its axis. and having said right angled bent portions perforated for the passage of the telescoping member, and a stop on said telescoping member between these two perforated portions.

5. Ina slack adjusting mechanism for railway brakes, the combination with the usual brake levers, rods and brake beams, of a telescoping bottom rod, means permitting. the lengthening of the bottom rod but normally preventing the shortcning thereof, and a take-up device com-.

prising a telescoping member connected at one end to one brake beam, and atthe other end provided with a lost motion connection to the other brake lever, said lost Tmotion connection comprising a barfastened at'one end to the brake beam, bent twice-at right angles to its axis, and having said right angled bent portions perforated for the passage of the telescoping member, and. a stop on said telescoping member between these two perforated portions, and said telescoping member comprising a stirrup fastened to the brake beam and perforated for the passage of the other member of the telescoping couple, and africtlon clutch dog mounted in said stirrup and engaging said other member.

Slgnedat New York, N. Y. this 19 day of NovembrlQOG.

A. PARKER-SMITH. Witnesses MANUEL'C. LOPEZ; M. G. CRAWFORD. 

